Showing papers by "University of New Brunswick published in 1974"
TL;DR: In this article, the initiation and propagation of microfractures and their contribution to material failure in compression are examined, and the early part of the fracture process, the lateral and the axial yield points of the stress-strain curves, are identified with the onset of micro-fracture, respectively at the tensile and the compressive stress concentrations of the elastic flaw boundary.
Abstract: The initiation and propagation of microfractures and their contribution to material failure in compression are examined. The early part of the fracture process, the lateral and the axial yield points of the stress-strain curves, are identified with the onset of microfracture, respectively at the tensile and the compressive stress concentrations of the elastic flaw boundary. Later stages, including the initiation of inclined shear fractures, the mobilization of total resistance and the reduction of strength to the residual level, are discussed in terms of a modified Coulomb model.
344 citations
TL;DR: It is concluded that chemoreceptors for the host attractants and the stimulants are located on the antennae and probably also on the maxillary and labial palpi in the female spruce budworm.
Abstract: The host selection of the female spruce budworm Choristoneura fumiferana (Clem.), Tortricidae, for oviposition is influenced both by the shape and the composition of the substrate. Needle extracts were bioassayed using artificial twigs. The active compounds are soluble in organic solvents and steam distillable. Synthetic D-α and L-β pinene occurring naturally in the extracts proved to be oviposition stimulants. The optical isomer L-α pinene did not show any activity. Ablation experiments led to the conclusion that chemoreceptors for the host attractants and the stimulants are located on the antennae and probably also on the maxillary and labial palpi.
Zusammenfassung
BEEINFLUSSUNG VON WIRTSPFLANZENREIZEN AUF DAS EIABLAGE-VERHALTEN DES NORDAMERIKANISCHEN TANNENKNOSPENWICKLERS
Die Weibchen von Choristoneura fumiferana bevorzugen fur die Eiablage ein nadeiformiges Substrat. Dabei spielen die mechanorezeptiven Sinneshaare auf den Ovipositor-Papillen vermutlich eine entscheidende Rolle. Petrolatherextrakte der Nadeloberflachen, Methanolextrakte und Wasserdampfdestillate ergaben eine erhohte Eiablage auf damit behandelten kunstlichen Nadelzweigen. Die aktiven Extraktfraktionen waren nur in organischen Losungsmitteln loslich. Fur die Attraktivitat und stimulierende Wirkung der Extrakte mussen verschiedene Substanzen verantwortlich sein, α- und β-Pinen wurden mit Hilfe des Gaschromatographen in den aktiven Fraktionen nachgewiesen. Synthetisches D-α und L-β Pinen waren beide aktiv. Dagegen ergab L-α Pinen bei den gepruften Konzentrationen keine erhohte Eiablage. Mit Hilfe von Ablationsexperimenten (Amputation, Uberziehen mit Paraffin) wurde versucht, die Chemorezeptoren fur die attraktiven und stimulierenden Stoffe zu lokalisieren. Dabei ergab sich, dass die Geruchsrezeptoren auf den Antennen und vermutlich auch auf den Labial-und Maxillarpalpen fur die Wirtswahl von Bedeutung zu sein scheinen.
83 citations
TL;DR: The use of input signals derived from maximum-length binary pseudorandom sequences is found to offer certain computational advantages, and a fast algorithm for the deconvolution of the output from such input signals is developed.
50 citations
TL;DR: An estimate of the number of active motor unitsN contributing to the myoelectric signal is obtained under the assumption that the individual motor-unit trains are statistically independent.
Abstract: A myoelectric signal, under isometric contraction of the muscle, is modelled as the output of a linear time-invariant system whose input is a stationary Poisson pulse train. The mean frequency γ of the Poisson pulse train and the transfer function of the linear system are evaluated using the spectral properties of the signal. An estimate of the number of active motor unitsN contributing to the myoelectric signal is obtained under the assumption that the individual motor-unit trains are statistically independent. The variation of γ andN with respect to load levels and electrode positions is examined experimentally.
47 citations
TL;DR: Using a stabilized CO2 laser, the band strengths, self-and N2-broadened halfwidths, and their variation with rotational quantum number have been measured for the 9·4 and 10·4-μm CO2 bands as mentioned in this paper.
Abstract: Using a stabilized CO2 laser, the band strengths, self- and N2-broadened half-widths, and their variation with rotational quantum number have been measured for the 9·4 and 10·4-μm CO2 bands. In addition, transmittance calculations have been carried out using these values for comparison with low-resolution laboratory spectra. Good agreement was obtained. Evidence is also presented indicating that the far wings of the 15-μm CO2 bands are sub-Lorentzian.
36 citations
TL;DR: In this article, three different mathematical models of an armature-controlled dc motor are considered: (i) a precise nonlinear model, (ii) a piecewise linear model, and (iii) a second-order linear model.
Abstract: Three different mathematical models of an armature-controlled dc motor are considered: (i) a precise nonlinear model, (ii) a piecewise linear model, and (iii) a second-order linear model. Experimental results are presented comparing the various models, and a range of applications for each is suggested.
33 citations
TL;DR: The Heath Steele massive sulphide deposit in northern New Brunswick lies conformably within a sedimentary-volcanic sequence of probable Ordovician age which has been metamorphosed to the greenschist stage.
29 citations
01 Mar 1974-Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology
TL;DR: A technique is described for the recording of action potentials from individual sensory receptors of the antenna of the spruce budworm, Choristoneurafumiferana, identified as type 4 on the basis of electrophysiological measurements and scanning electron microscopy.
Abstract: A technique is described for the recording of action potentials from individual sensory receptors of the antenna of the spruce budworm,Choristoneura
fumiferana (Clem.). The antennae of adult male spruce budworm, are shown to bear olfactory receptors which respond to the female sex pheromone, trans-11-tetradecenal. The receptors are long sensilla trichodea, identified as type 4 on the basis of electrophysiological measurements and scanning electron microscopy. A minimum concentration of 10−8mg of pheromone is required to elicit a response. Once the threshold concentration for the receptor is reached there is a correlation between stimulus concentration and the intensity of the response within the first 400 msec of the response.
27 citations
01 Dec 1974
TL;DR: This paper reviews and analyzes some existing mathematical models used for the combination of terrestrial and satellite networks and finds that they all contain three rotations, three translations and a scale scale.
Abstract: This paper reviews and analyzes some existing mathematical models used for the combination of terrestrial and satellite networks. They all contain three rotations, three translations and a scale fa...
26 citations
24 citations
01 Jul 1974
TL;DR: In this article, the authors investigated the stability of limit cycles in nonlinear feedback systems with several describing function (d.f.) predicted limit cycle solutions and showed that for a single-frequency limit cycle the necessary conditions for stability of Loeb and Gelb could be satisfied yet the limit cycle was unstable.
Abstract: This paper investigates the stability of limit cycles in nonlinear feedback systems with several describing function (d.f.) predicted limit cycle solutions. The investigations showed that for a single-frequency limit cycle the necessary conditions for stability of Loeb and Gelb could be satisfied yet the limit cycle was unstable. Also the simple and often used graphical criterion was found to be incorrect. On the other hand, the incremental-describing function (i.d.f.) method used for both asynchronous and synchronous perturbations gave sufficient conditions, within the expected d.f. accuracy, for all the situations. It is further shown that the synchronous i.d.f. and the Loeb criterion are normally identical. The combined mode limit cycle oscillations were also satisfactorily predicted by a twoinput d.f. and i.d.f.
TL;DR: In this article, a sequence of irregular nodular limestones in the Silurian of northern New Brunswick appear to have undergone early marine lithification and computed porosities at the time of lithification based on the ratio of carbonate to insoluble residues suggest lithification depths within a few tens of feet of the sediment-water interface.
Abstract: A sequence of irregular nodular limestones in the Silurian of northern New Brunswick appear to have undergone early marine lithification. Nodules and crusts formed soon after deposition in the argillaceous lime sediments by sporadic diagenetic precipitation of calcium carbonate and were subsequently modified by differential compaction and minor flowage.
While lack of both borings and encrusting organisms on the nodules indicates they were not ‘hard grounds’, computed porosities at the time of lithification based on the ratio of carbonate to insoluble residues suggest lithification depths within a few tens of feet of the sediment-water interface. Consideration of the availability of calcium carbonate suggests lithification very close to the sediment surface.
TL;DR: The absorption by ozone of the P(36, P(38), and P(40) CO2 94-μm laser lines has been studied in this paper, where it was found that the P40 line was within 17 ± 13 MHz of the 119,2 − 129,3ν3 ozone line.
Abstract: The absorption by ozone of the P(36), P(38), and P(40) CO2 94-μm laser lines has been studied It was found that the P(40) line was within 17 ± 13 MHz of the 119,2 − 129,3ν3 ozone line In addition the intensity of the 119,2 − 129,3 ozone line was found to be 0108 cm−1 (atm cm)−1 at 298 K, and it was located at 10273825 ± 00009 cm−1 The ν3 ozone band intensity was determined to be 326 ± 27 cm−1 (atm cm)−1 at 298 K
TL;DR: In this article, a molecular sieve adsorption column operated isothermally under conditions of micropore diffusion control is reported, where the breakthrough curve is very sensitive to quite small deviations from linearity and regeneration is much slower than saturation.
TL;DR: In this paper, a conceptual framework is proposed: "reserves" are restricted to known currently exploitable deposits, "known resources" are reserves plus currently non-exploitable deposits; total resources are known resources plus all deposits not yet discovered.
TL;DR: In this article, the authors reported that bis(perfluoroethyl) ditelluride and chlorine monofluoride react in a 1:6 ratio at -78C to give C2F5TeF3 as well as small amounts of trans C2Fs5TeClF4 and TeClF5.
TL;DR: The Albert Formation of New Brunswick, Canada, has been shown to be mainly limnitic (lacustrine) in origin this article, and it is concluded that the Albert Formation was deposited in a tropical or sub-tropical environment over a period of several hundred thousand years.
Abstract: Recent work on the Lower Carboniferous Albert Formation of New Brunswick, Canada, has confirmed it to be mainly limnitic (lacustrine) in origin. Within its smallsized basin (ca. 4,000 sq. km.) over 1,300 m of sediment were deposited. These greyish beds are stratigraphically bounded below, above, and toward the south by terrestrial, mainly redbed, formations. Abundant organic varves in a dolomitic marlstone are present, and in places contain articulated fish skeletons. Elsewhere, symmetrical ripple-marks predominate, testifying to gentle water-current movements. The crossopterygianLatvius sp. dates basal beds, in part at least, as Upper Devonian. Ostracodes from an upper member —Euestheria sp., cf.E. lirella; Hilboldtina sp.,Carbonita sp., cf.C. subula — are from the Carboniferous. It is concluded that the Albert Formation was deposited in a tropical or sub-tropical environment, probably in an east-trending rift valley or fault-block basin, over a period of several hundred thousand years, and terminating with evaporitic deposits, at least a part of which were non-marine in origin.
Journal Article•
TL;DR: In this paper, the authors reviewed the Precambrian and Paleozoic stratigraphy and structure of New Brunswick against the background of the theory of plate tectonics and concluded that as a result of successive Penobscot, Taconic and Acadian orogenic disturbances parts of Paleoamerica and Paleoeurope are so sutured that the intervening oceanic crust has either been entirely obducted onto the continents or subducted below them.
Abstract: The paper reviews the Precambrian and Paleozoic stratigraphy and structure of New Brunswick against the background of the theory of plate tectonics. The major subdivisions of the Appalachian-Caledonian orogenic belt are examined and a conclusion is reached that as a result of successive Penobscot, Taconic and Acadian orogenic disturbances parts of Paleoamerica and Paleoeurope are so sutured that the formerly intervening oceanic crust has either been entirely obducted onto the continents or subducted below them. The evolution of the orogenic belt in New Brunswick and adjacent regions can be explained with reference to the formation of successive volcanic arcs.
TL;DR: Body weight in Malaclemys terrapin progressively declined during extended stays in sea water, whereas in fresh water body weight remained stable, and initially, plasma sodium, and osmotic pressure increased in animals acclimated to seaWater, but after this phase remained stable for periods up to 6 months in seaWater.
TL;DR: Electrophysiological investigations show that chemosensitive cells in tarsal setae of the spruce budworm are sensitive to at least two salts and possibly water.
TL;DR: In this article, the authors performed a rotational analysis on the emission spectra of the 0-0, 1-1, 2-2, and 3-3 bands of the β system (c1Φ - a1Δ) of the TiO molecule excited in a microwave discharge through a mixture of helium, oxygen and TiCl4 vapor.
TL;DR: In this article, the design of linear regulators, optimal with respect to a time-multiplied quadratic performance index, is considered and a suitably modified index is used and a design which is optimal in an average sense is obtained.
Abstract: The design of linear regulators, optimal with respect to a time-multiplied quadratic performance index, is considered. Since it is not possible to minimize the normal form of the index with constant feedback gains, a suitably modified index is used and a design which is optimal in an average sense is obtained.
TL;DR: In this article, an analytical method is developed for predicting the ultimate strength of eccentrically loaded fillet weld connections not free to deform in the compression zone, using the true load-deformation response of the welds rather than some idealized one.
Abstract: An analytical method is developed for predicting the ultimate strength of eccentrically loaded fillet weld connections not free to deform in the compression zone. The method uses the true load-deformation response of the welds rather than some idealized one. The validity of the approach has been verified by a testing program using 16 full-size specimens. Comparison of the ultimate strength obtained by this method with allowable loads calculated assuming elastic behavior shows that the resulting factor of safety is both high and inconsistent.
TL;DR: In this article, a modification of the standard CNDO/2 method was proposed, in which pairs of atoms associated with the same molecule and with different molecules are differentiated, which leads to reduced intermolecular bonding and provides reasonable stabilization energies and inter-planar separations.
Abstract: The standard CNDO/2 method is shown to be unable to produce meaningful potential curves for π-π-type molecular complexes. A modification of this method in which pairs of atoms associated with the same molecule and with different molecules are differentiated leads to reduced intermolecular bonding and provides reasonable stabilization energies and intermolecular separations. Calculations based on this modified method indicate that benzene-borazine and borazine-borazine complexes in which the molecules are symmetrically disposed in parallel planes can exist in the ground state. The stabilization energies are calculated to be in the range 2–5 kcal/mole for benzene-borazine and 5–18 kcal/mole for borazine-borazine, with interplanar separations near 3 A in both cases.
TL;DR: In this article, the Craya-Curtet number for a combustion system has been derived from an overall analysis by assuming that the reduced density distribution in the system can be represented by a single mean value.
Abstract: The analyses of Thring and Newby and Craya and Curtet on the confined turbulent jet system are reviewed The Craya-Curtet number for a combustion system has been derived from an overall analysis by assuming that the reduced density distribution in the system can be represented by a single mean value The axial progress of combustion and the mass flow rates in the central region of the jet, calculated from the data on the isothermal confined jet system by using the above mentioned “Combustion Craya-Curtet number”, have been found to be in reasonably good agreement with the values calculated from experimental measurements taken in a cylindrical test furnace The rate of entrainment in the combustion system has been correlated by modifying the free jet equation of Ricou and Spalding
TL;DR: It was possible to demonstrate that certain histone fractions are preferentially retained in either exponential or stationary-phase nuclei by introducing various concentrations of citrate and divalent cations in the medium used for cell lysis and isolation of nuclei prior to histone extraction.
01 Dec 1974
TL;DR: In this article, the classical problem of positioning horizontal geodetic datums is treated as a classical problem when dealing with the usual horizontal control networks, as opposed to the problem we face in this paper.
Abstract: This paper treats the classical problem of positioning horizontal geodetic datums. By ‘classical problem’ we mean the problem we face when dealing with the usual horizontal control networks, as opp...
TL;DR: In this article, the gamma-ray coincidence spectrometry was used to measure the Al 26 activity of 30 stony meteorites (13 bronzite, 13 hypersthene, 1 carbonaceous and 1 enstatite chondrite, and 2 achondrites).
TL;DR: In this paper, the authors report the results of an investigation to determine the optimum combinations of microwave power level and exposure duration required for germination enhancement of various tree seeds common in eastern Canada.
Abstract: This paper reports the results of an investigation to determine the optimum combinations of microwave power level and exposure duration required for germination enhancement of various tree seeds common in eastern Canada. Improved exposure methods are used which allow the determination of electric field at the seed sample. A microwave technique for measuring very low moisture contents (3% to 10%) of tree seeds also is described.